1. Field of the Invention
The present invention generally relates to a hard disk drive unit and, more particularly, to a 3.5-inch hard disk drive unit using a hard disk having a diameter of 3.5 inches.
2. Description of the Related Art
FIG. 1 is a cross-sectional view of a conventional 3.5-inch hard disk drive unit 10. The hard disk drive unit 10 has a mechanism part 11 and an electronic circuit part 30.
The mechanism part 11 comprises: a base 12; a motor 13 fixed to the base 12 for rotating a hard disk 14 having a diameter of 3.5 inches and fixed to the motor 13; a carriage arm 16 having a head slider 15 at an extreme end thereof; a magnetic circuit 17 for reciprocally moving the carriage arm 16; and a cover 18 covering the hard disk 14, the carriage arm 16 and the magnetic circuit 17. In FIG. 1, although only one hard disk 14 is shown, a storage capacity can be increased by increasing the number of hard disks. Manufacturers of hard disk drive units provide versatile apparatus lineups by changing the number of hard disks in this way using the common parts as much as possible.
A hard disk drive unit 10 further comprises a printed circuit board unit 20 containing a printed circuit board 21. A plurality of electronic parts are mounted on a surface of a printed circuit board 21, and the connector 22 is mounted in the end of a printed circuit board 21. The printed circuit board 20 is fixed to an undersurface of a base 12, and a connector 22 is exposed at an end surface of the hard disk drive unit 10. The height H1 of the hard disk drive unit 10 is 1 inch. The printed circuit board unit 20 constitutes an electronic circuit part 30.
As shown in FIG. 2, the electronic circuit part 30 comprises an interface part 31, which interfaces with a higher order system 40, and a control part 32, which controls an operation of the mechanism part 101 and data reading and the writing operations. As shown in FIG. 2, the printed circuit board unit 20 comprises: a hard disk controller (HDC) 51; a RAM 52 as a buffer for temporarily storing data; a ROM for storing programs for controlling an MPU 54; a read channel 55; a servo controller (SVC) 56; and drivers 57 and 58.
The interface part 31 comprises a hard disk controller (HDC) 51 for a 3.5-inch hard disk drive unit, and a connector 22 for a 3.5-inch hard disk drive unit. A control part 32 consists of the MPU 54 and the ROM 53. The hard disk 14 is rotated by the motor 13 at a high speed. The carriage arm 16 is reciprocally rotatable by the magnetic circuit 17. The head slider 15 is moved in a radial direction of the hard disk 14 while being floated above the surface of the hard disk 14 so as to scan a target track to carry out information writing and reading. The read reproduction signal is supplied to a head IC 19 so as to be amplified, and, thereafter, the amplified signal is supplied to a read channel 55.
The 3.5-inch hard disk drive unit 10 having the above-mentioned composition has a feature that a storage capacity is large since the diameter of the hard disk 14 is as large as 3.5 inches. Moreover, the 3.5-inch hard disk drive unit 10 is operated by an input power supply voltage of 12V.
The 3.5-inch hard disk drive unit 10 has a space having a height of 1 inch, and also has a connector into which the connector 22 for 3.5-inch hard disk drive units fits so as to be incorporated into an apparatus such as a personal computer which can supply an input power supply voltage of 12V. Moreover, for example, the 3.5-inch hard disk drive unit 10 is used by being incorporated into a digital television set or a digital audio apparatus.
Although the above-mentioned 3.5-inch hard disk drive unit 10 has a large storage capacity as compared with a 2.5-inch hard disk drive unit, there is a problem in that a size is large and a power consumption is also large. On the contrary, although a 2.5-inch hard disk drive unit has a smaller size and less power consumption than the 3.5-inch hard disk drive unit, there is a problem in that a storage capacity is small.
Furthermore, the same housing is used for both a hard disk drive unit having a single hard disk and a hard disk drive unit having a plurality of hard disks. Therefore, there is a large empty space in the housing of the hard disk drive unit having a single hard disk. Moreover, in order to balance a rotation of a carriage arm, a dummy head is provided, which causes a problem that there is an unnecessary part cost.
Moreover, the above-mentioned problem has been closed-up since a sufficiently large storage capacity can be obtained with less number of hard disks and the demand for a hard disk drive unit of a single 3.5-inch hard disk has been increased in association with the high density recording in recent years.
It is a general object of the present invention to provide an improved and useful hard disk drive unit in which the above-mentioned problems are eliminated.
A more specific object of the present invention is to provide a 3.5-inch hard disk drive unit which has a small power consumption and can be incorporated into a small space.
In order to achieve the above-mentioned objects, there is provided according to one aspect of the present invention a hard disk drive apparatus comprising: a mechanism part provided in a housing, the mechanism part comprising a hard disk having a diameter of 3.5 inches, a motor for rotating the hard disk, a carriage arm having a head slider mounted on an end thereof and a magnetic circuit reciprocally rotates the carriage arm; and an electronic circuit part controlling the mechanism part, the electronic circuit part having an interface part, which is prepared for a 2.5-inch hard disk drive unit, so as to interface with an upper order system.
According to the above-mentioned invention, the hard disc drive unit has a storage capacity larger than that of a 2.5-inch hard disk drive unit. Additionally, a power consumption of the hard disk drive unit is less than a conventional 3.5-inch hard disk unit. Further the hard disk drive unit having a 3.5-inch disk can be connected to a higher order system of a 2.5-inch hard disk drive unit.
Additionally, there is provided according to another aspect of the present invention a hard disk drive unit comprising: a housing having a height of about xc2xd inch; and a mechanism part provided in the housing, the mechanism part comprising a hard disk having a diameter of 3.5inches, a motor for rotating the hard disk, a carriage arm having a head slider mounted on an end thereof and a magnetic circuit reciprocally rotates the carriage arm.
According to the above-mentioned invention, the hard disk drive unit having a 3.5-inch hard disk can be incorporated into a space having a height of xc2xd inch. Thus, the hard disk drive unit according to the present invention can replace a 2.5-inch hard disk drive unit.
Additionally, there is provided according to another aspect of the present invention a hard disk drive unit comprising: a housing having a substantially rectangular horizontal cross section; a mechanism part provided in the housing, the mechanism part comprising a hard disk having a diameter of 3.5 inches, a motor for rotating the hard disk, a carriage arm having a head slider mounted on an end thereof and a magnetic circuit reciprocally rotates the carriage arm; an electronic circuit part provided in the housing so as to control the mechanism part; and a connector exposed on a side surface of the housing corresponding to a long side of the rectangular shape so as to connect the electronic circuit part to an external device.
According to the above-mentioned invention, two kinds of 3.5-inch hard disk units can be provided, one being the 3.5-inch hard disk drive unit having a connector exposed on the short side and the other being the 3.5-inch hard disk drive unit having a connector exposed on the long side. Therefore, the restrictions in the arrangement of the connector of a 2.5-inch hard disk drive unit for the higher order system are relaxed.
Additionally, there is provided according to another aspect of the present invention, a hard disk drive unit comprising: a housing; a mechanism part provided in the housing, the mechanism part comprising a hard disk, a motor for rotating the hard disk, a carriage arm having a head slider mounted on an end thereof and a magnetic circuit reciprocally rotates the carriage arm; and an electronic circuit part provided in the housing so as to control the mechanism part, wherein the carriage arm includes a head slider mounting part and a voice coil attachment part integrally formed with each other by a metal plate being press punched so that the head slider mounting part and the voice coil attachment part are arranged opposite to each other with respect to a rotational axis of the carriage arm.
According to the present invention, since the carriage arm has a single integrated construction which can be formed by press punching a metal plate. Thus, a manufacturing cost of the carriage arm can be reduced, which results in a cost reduction of the hard disc drive unit.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the following drawings.